JP3932883B2 - Flooring - Google Patents

Description

【００６５】
また、上記各床材を用いて施工した床面上を素足で歩き、触感及び歩行感を調べたところ、比較例３の床材について冷触感及び歩行感の悪さが、比較例５の床材について歩行感の悪さが、それぞれ指摘されたが、その他は特に問題なしの結果であった。
【００６６】
【発明の効果】
以上詳細に説明したように、本発明の床材は、熱可塑性樹脂及び木質系充填剤を含む木質樹脂発泡成形体を基材とし、その表面に基材の主成分である熱可塑性樹脂と同系の熱可塑性樹脂からなる化粧シートを積層してなることにより、木質感や切削性、リサイクル適性に優れていることに加え、その芯部及び表層部の発泡倍率や厚さを特定範囲とすると共に、基材の主成分である熱可塑性樹脂の曲げ初期弾性率を特定範囲としたことにより、断熱性（暖触感）、歩行感、表面硬度、耐衝撃性、耐傷付き性、耐圧痕性、施工適性等の各面でバランスの取れた、従来の木質系フローリング材の代替品として好適な優れた性能を有する床材を提供することができるという実用上の顕著な利点を有するものである。
【図面の簡単な説明】
【図１】本発明の床材の実施の形態を示す側断面図である。
【符号の説明】
１ 木質樹脂発泡成形体
１１ 芯部
１２ 表層部
１３ 熱可塑性樹脂
１４ 木質系充填剤
１５ 気泡
２ 化粧シート[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a flooring for use on an indoor floor surface in a building such as a detached house, a condominium, an apartment, a recreational facility, an office building, or a store.
[0002]
[Prior art]
At present, wood flooring materials are most prevalent as floor materials for indoor floors in buildings such as detached houses. Specifically, the wooden flooring material has a thickness of about several hundred μm to several mm on a wooden base material such as a solid plate of natural wood having a thickness of about 5 to 15 mm or a laminated plywood having a thickness of about 5 to 15 mm. It is a thing stuck with a veneer of natural wood, or a painted product thereof.
[0003]
These wood-based flooring materials using natural wood have been widely accepted by consumers since the design of the surface is the most natural, familiar and beautiful design of natural wood. However, it is easy to discolor when exposed to sunlight, and when it gets wet, it tends to swell, crack, warp, corrode, peel off the veneer, etc., especially to areas around the water such as bathroom dressing rooms, washrooms, kitchens, etc. It has been pointed out that there are problems in use, and that the quality, price, and supply amount of color tone and grain shape are unstable because it is a natural material.
[0004]
Particularly in recent years, as social interest in global environmental protection issues has increased, mass consumption of natural timber that leads to environmental destruction has become a perception, and the use of recycled resources in the field of building materials such as flooring The approach to has come to be required. However, it is extremely difficult to recycle the wood flooring material as a flooring material, both technically and economically, and at most it is only crushed and recycled as a raw material for particleboard. This is also due to the lack of progress in application development in response to the rapid increase in supply in recent years, so there is an excess inventory, and recycling is in a deadlock situation, and most of the final disposal is done by landfill or incineration. .
[0005]
Therefore, there is a strong social demand for the development of a recyclable flooring that can be reused as a raw material for the same kind of flooring after use. In order to meet these demands, the present inventors have already made a thermoplastic resin similar to the thermoplastic resin contained in the wooden resin molded article on the surface of the wooden resin molded article containing the thermoplastic resin and the wooden filler. A flooring made by laminating decorative sheets mainly composed of resin was proposed (Japanese Patent Application No. 2000-178362).
[0006]
Since this flooring is mainly composed of thermoplastic resin, it has excellent water resistance and weather resistance, and it can supply a large quantity of products with stable quality in terms of physical properties and design, such as cutting and nailing. The processability is equivalent to that of the wood-based flooring material, and it has excellent recyclability such that it can be pulverized as it is after use and reused as a molding material for the wood resin molding.
[0007]
In addition, the present inventors have further said wood resin molding for the purpose of improving adhesiveness by water-based or solvent-based adhesives, heat insulating property giving warm touch similar to natural wood, elasticity giving a pleasant walking feeling, etc. A flooring using a wood resin foam molded body obtained by foaming the body as a base material has already been proposed (Japanese Patent Application No. 2000-317482).
[0008]
However, as a result of subsequent trial production, it was found that the flooring material using the above-mentioned wood resin foam molded article also has the following problems. That is, in order to improve the heat insulating property and walking feeling of the flooring material, it is advantageous to increase the expansion ratio of the wood resin foam molding and / or to use a soft thermoplastic resin having a low elastic modulus. However, since the hardness of the wood resin foamed molded article is lowered, the scratch resistance and pressure scar resistance on the surface of the flooring material (because it is difficult to place heavy load marks or caster marks). Therefore, it is difficult to achieve both heat insulation and a feeling of walking with scratch resistance and pressure resistance.
[0009]
[Problems to be solved by the invention]
The present invention has been made in order to solve the above-described problems in the prior art, and is a flooring based on a wood resin foam molded article excellent in wood texture and recyclability, The present invention intends to provide a flooring material having excellent physical properties with a good balance in each aspect such as property, walking feeling, scratch resistance, and pressure scar resistance.
[0010]
[Means for Solving the Problems]
The flooring material of the present invention contains a thermoplastic resin and a wood filler, and has the same heat as the thermoplastic resin contained in the wood resin foam molding on the surface of the foamed wood resin foam molding. A flooring material in which a decorative sheet mainly composed of a plastic resin is laminated, wherein the wood resin foam molded article has a foaming ratio of 1.0 to 1.1 times and a thickness of 0.1 to 2 mm. And the thermoplastic resin contained in the wood resin foam molded article is a polyolefin-based polyolefin having an initial flexural modulus of 700 to 3000 MPa. It is a resin.
[0011]
In particular, in the above flooring material, the wood filler has an average particle size of 1 to 200 μm and is blended in an amount of 10 to 500 parts by weight with respect to 100 parts by weight of the thermoplastic resin. It is.
[0012]
In particular, in the floor material, the wood resin foam molded article is formed by a Celca process.
[0013]
In particular, in the flooring, the decorative sheet has a thickness of 0.05 to 0.3 mm.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
As shown in FIG. 1, the basic structure of the flooring material of the present invention is formed by foaming a mixture composition of a thermoplastic resin 13 and a wooden filler 14 (there are bubbles 15 inside). The decorative sheet 2 made of a thermoplastic resin similar to the thermoplastic resin 13 is laminated on the surface of the wood resin foam molded body 1.
[0015]
The woody resin foam molded body 1 has a layer structure having a surface layer portion 12 that is a portion with a low expansion ratio on the surface side of the core portion 11 that is a portion with a high expansion ratio. Is 1.2 to 3.0 times, the expansion ratio of the surface layer portion 12 is 1.0 to 1.1 times, and the thickness of the surface layer portion 12 is 0.1 to 2 mm. Further, the thermoplastic resin 13 is made of a polyolefin resin having an initial flexural modulus of 700 to 3000 MPa.
[0016]
In the present invention, as described above, the wood resin foam molded article 1 has a foaming ratio of 1.0 to 1.1 times and a thickness on the surface of the core 11 having a foaming ratio of 1.2 to 3.0 times. It is important to have a layer structure in which a surface layer portion 12 of 0.1 to 2 mm is formed. As shown in FIG. 1, the surface layer portion 12 is not necessarily provided so as to surround the entire surface of the core portion 11, and may be formed at least on the upper surface of the core portion 11. In addition, only the upper surface of the core portion 11 may be formed from the upper surface to a part or all of the side surface.
[0017]
If the expansion ratio of the core 11 is less than 1.2 times, or if the thickness of the surface layer 12 exceeds 2 mm, it may cause an unpleasant cold touch when touched with bare feet due to insufficient heat insulation. In addition to causing the floor material to become hard as a whole, the impact on the human body during walking cannot be absorbed, the feeling of walking will be inferior, the impact due to falling items etc. will not be absorbed, and it will be easy to break It is also uneconomical because the flooring weight increases and the amount of material used increases.
[0018]
On the other hand, if the expansion ratio of the core 11 exceeds 3.0, the expansion ratio of the surface layer 12 exceeds 1.1, or the thickness of the surface layer 12 is less than 0.1 mm, the flooring Due to lack of rigidity and surface hardness, deterioration of scratch resistance and pressure dent resistance, and deterioration of dimensional stability, due to gaps between floor materials due to temperature changes and by pushing up between floor materials This is because it may cause floating or the like.
[0019]
Moreover, it is important that the thermoplastic resin 13 contained in the wood resin foam molded body 1 is made of a polyolefin-based resin having an initial flexural modulus of 700 to 3000 MPa. If the initial flexural modulus is less than 700 MPa, the rigidity and surface hardness as a flooring material are insufficient, which causes deterioration of scratch resistance and pressure scar resistance. On the other hand, even if the initial flexural modulus exceeds 3000 MPa, the flooring material becomes hard as a whole, and the feeling of walking is deteriorated, or the impact resistance is lowered and the crack is easily broken.
[0020]
In addition, the thickness of the woody resin foam molded body 1 is generally about 2 to 30 mm, like the conventional ordinary flooring material, and is often about 3 to 15 mm. And it is desirable for the thickness of the core layer 11 in the wood resin foam molded body 1 to be half or more of the thickness of the whole wood resin foam molded body 1.
[0021]
In the present invention, examples of the polyolefin-based thermoplastic resin 13 used for the wood resin foam molded article 1 include polyethylene, polypropylene, polybutene, polyisoprene ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, ethylene-α. Olefin copolymer, propylene-α olefin copolymer, ethylene-ethyl acrylate copolymer, those modified with acid for the purpose of improving adhesion, or ionomer can be selected as appropriate. Mixing seeds is also acceptable.
[0022]
Among them, polypropylene, such as homopolypropylene, random polypropylene, block polypropylene, and propylene-α-olefin copolymer, in terms of rigidity, surface hardness, and dimensional stability (low linear expansion coefficient) required for flooring. Resin is most suitable.
[0023]
In particular, in order to increase the adhesion, for example, the blend ratio of the acid-modified resin such as polyethylene or polypropylene obtained by graft copolymerization with an unsaturated carboxylic acid such as maleic acid or its anhydride is increased, and the resin itself It is desirable to impart polarity to the wood and to improve the adhesion to the wood filler.
[0024]
Further, in the present invention, as will be described later, since the woody resin foam molded body 1 needs to be foamed, the thermoplastic resin 13 is required to have foamability. In general, in order to improve foamability, it is desirable that the thermoplastic resin 13 has a high melt tension, and in particular, when gas leakage or the like when the wood-based filler 14 is highly filled is concerned, a long chain due to electron beam crosslinking is used. It is desirable to adjust the melt tension as necessary by a known method such as the use of a grade with branching introduced, the control of the molecular weight distribution, or the blend of a fluorine-based additive that increases the melt tension. In addition, when the foam molding method by the Selka process described later is used, there is an advantage that good foaming is possible even with a resin having a low melt tension, as compared with a sheet foam molding method and a normal profile foam extrusion molding method.
[0025]
In the present invention, the material of the wood-based filler 14 used for the wood resin foam molded body 1 can be selected without any particular limitation, but generally the wood is broken by a cutter mill or the like, This is pulverized by a ball mill or an impeller mill, etc. and used in a fine powder form (wood powder).
[0026]
It is important that the average particle diameter of the wood filler 14 is 1 to 200 μm, preferably 10 to 150 μm. Those having an average particle size of less than 1 μm are difficult to handle, and especially when the amount of the wood-based filler is large, if the dispersion into the resin is poor, the mechanical strength of the wood-resin foamed molded product to be produced Decrease occurs. On the other hand, if it is larger than 200 μm, the homogeneity, flatness and mechanical strength of the molded product are lowered.
[0027]
Moreover, about the compounding quantity of the wood type filler 14, although it can select suitably from 10 weight part to 500 weight part with respect to 100 weight part of the thermoplastic resin 13, in order to improve a moldability and homogeneity. The wood-based filler 14 is desirably blended in an amount of 30 to 300 parts by weight, more preferably 50 to 150 parts by weight with respect to 100 parts by weight of the thermoplastic resin 13.
[0028]
If the amount of the wood filler 14 is too large, the flexural modulus of the flooring will increase and the flexibility will be lost, so the workability will deteriorate (especially during construction in the corner or when replacing one piece) , It becomes difficult to bend the flooring and install it, and it is easy to break when bent. On the other hand, if the amount is too small, the coefficient of linear expansion will increase and the dimensional stability will decrease, which may cause a gap between the flooring materials or a lift due to the thrusting of the flooring materials due to temperature changes. Because it becomes.
[0029]
In the present invention, in addition to the thermoplastic resin 13 and the wood filler 14, a foaming agent is added to the foamable wood resin composition for molding the wood resin foam molded article 1, and foaming is performed in the molding process. Is done.
[0030]
In the present invention, the molding and foaming method of the wood resin foam molded body 1 composed of two layers of the core part 11 having a high foaming ratio and the surface layer part 12 having a low foaming ratio are not particularly limited. For example, the blending amount of the foaming agent is changed. A method of laminating a plurality of types of foamable wood resin compositions separately by an extrusion method or an injection molding method or the like, a sequential extrusion method or a coextrusion method using a plurality of types of foamable wood resin compositions, etc. However, it is most preferable to use a Celca process as a molding method that can be molded continuously and stably in a single process using a single type of expandable wood resin composition.
[0031]
The above-mentioned Celca process is an extrusion mold having an outlet dimension that is substantially the same as or slightly smaller than the inlet dimension of the cooling sizing mold, and is in close contact with the cooling sizing mold. Foaming the foamable resin composition by extruding the foamable resin composition into the cooling sizing mold in a state where the foaming is hardly progressing, and mainly foaming inside the cooling sizing mold Extrusion method.
[0032]
Depending on the thickness of the molded product and the expansion ratio, an extrusion die with a torpedo (also called mandrel or core) is used inside the extrusion die, or resin is extruded through a hole provided in the torpedo. May be used.
[0033]
In the foam extrusion molding method of this Celca process, the surface layer portion of the molded body is hardly foamed because it is pressed against the inner surface of the cooling sizing mold immediately after being extruded from the extrusion mold, and foaming is mainly performed inside the molded body ( It is characterized by automatically forming a non-foamed or low-foaming surface layer on the surface, and a high-foaming core inside, which is also called the inward forming process. Yes.
[0034]
In the present invention, the foamable wood resin composition used for molding the wood resin foam molded article 1 includes a heat stabilizer, an acid neutralizer, an ultraviolet absorber, a light stabilizer, a pigment, a dye, and the like as necessary. Coloring agents, fillers, antistatic agents, lubricants, nucleating agents, flame retardants, antiblocking agents, dehydrating agents, light scattering agents for making translucent, gloss adjusting agents, and the like can also be added.
[0035]
Among these additives, hindered phenols, sulfurs, phosphoruss, etc. as heat stabilizers, stearic acid metal salts, hydrotalcite, etc. as acid neutralizers, benzotriazoles, benzoates as ultraviolet absorbers, etc. Benzophenone, triazine, etc., and light stabilizers include hindered amines.
[0036]
Examples of flame retardants include halogen flame retardants, phosphorus flame retardants, and chlorine flame retardants. Fillers include calcium carbonate, silica, titanium oxide, barium sulfate, zinc oxide, alumina, talc, mica, magnesium silicate, and titanium. Examples include potassium acid, magnesium sulfate, aluminum hydroxide, magnesium hydroxide, iron oxide, carbon black, and metal powder.
[0037]
As lubricants, hydrocarbon lubricants, fatty acids, higher alcohols, fatty acid amides, metal soaps, esters, fluorines, etc. As nucleating agents, carboxylate metal salts, sorbitol, phosphate ester metal salts, etc. Examples of pigments include condensed azo, insoluble azo, quinacridone, isoindoline, anthraquinone, imidazolone, cobalt, phthalocyanine, carbon, titanium oxide, iron oxide, mica, and other pearl pigments. Generally used in combination.
[0038]
Any known technique can be used for the foaming technique. In general, chemical foaming can be classified into chemical foaming, which generates gas by thermal decomposition or chemical reaction, and physical foaming, which heats low-boiling liquids to vaporize them, and chemical foaming agents include inorganic sodium bicarbonate and ammonium carbonate. Ammonium bicarbonate, ammonium nitrite, sodium borohydride, light metals, azide compounds, etc., and organic foaming agents such as azo, nitroso, hydrazide, etc. can be used in any combination.
[0039]
In particular, physical foaming is mainly used for foaming at a high foaming ratio exceeding 2 times, and carbon dioxide gas and aliphatic hydrocarbons are mainly used as foaming agents. In addition, a chemical foaming agent is often used in combination with physical foaming to adjust the cell shape of the foam.
[0040]
In the present invention, the kneading of the thermoplastic resin 13, the wood filler 14, the foaming agent and other additives constituting the foamable wood resin composition is not particularly limited, but the kneading is performed by a Banbury mixer, and the pelletizer. In general, a pelletizing method or a twin screw extrusion kneader is used for mixing and pelletizing. Moreover, since the wood filler 14 causes foaming during pelletization when the moisture content is large, it is desirable to suppress the moisture content to 8% or less in advance with a dryer or a hopper dryer before kneading.
[0041]
A decorative sheet 2 mainly composed of a thermoplastic resin similar to the thermoplastic resin 13 contained in the wood resin foam molded body 1 is laminated on the surface of the wood resin foam molded body 1, and the flooring of the present invention is formed. Composed. It is important that the thermoplastic resin of the same type can be recycled without significant change in physical properties even when mixed with the thermoplastic resin 13 contained in the wood resin foam molded body 1.
[0042]
Specifically, for example, polyethylene, polypropylene, polybutene, polyisoprene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, ethylene-α olefin copolymer, propylene-α olefin copolymer, ethylene-ethyl acrylate. It is possible to appropriately select from various polyolefin resins such as copolymers, those acid-modified for the purpose of improving adhesiveness, ionomers, mixtures thereof, copolymers, and the like. The same kind or different kind of resin selected from the above can be used as the thermoplastic resin for the woody resin foam molded body 1 and the decorative sheet 2.
[0043]
The important points about the decorative sheet 2 to be laminated are that, as described above, the use of a thermoplastic resin similar to the thermoplastic resin 13 contained mainly in the wood resin foam molded article 1, and the grain, stone, texture, abstract Since the design such as a pattern is printed, there is no restriction on the configuration of the decorative sheet itself.
[0044]
This decorative sheet 2 is, for example, a single-layer decorative sheet obtained by printing on a colored sheet, or a sheet obtained by printing a colored sheet on a transparent sheet bonded by a dry lamination method, an extrusion lamination method, a thermal lamination method, or the like. It can be appropriately selected depending on the application from a single-layer decorative sheet, a back-printed single-layer decorative sheet printed on the back surface of a transparent sheet, and the like.
[0045]
At this time, if the decorative sheet 2 has sufficient concealment, a stable design reproduction can be achieved. Conversely, if the decorative sheet has transparency, it is possible to express the design using the wood texture of the wood resin foam molded body 1. Become.
[0046]
Ink used for printing pattern, pattern, coloring, etc. of decorative sheet 2 such as grain pattern, nitrified cotton, cellulose, vinyl chloride-vinyl acetate copolymer, polyvinyl butyral, polyurethane, acrylic, polyester, etc. alone Or what is necessary is just to select suitably from each modified | denatured substance. These may be any of aqueous, solvent-based and emulsion types, and can be arbitrarily selected from a one-component type or a two-component type using a curing agent. Further, the ink can be cured by irradiation with ultraviolet rays or electron beams.
[0047]
Among them, the most general method is a method of curing with an isocyanate using a urethane-based ink. In addition to these binders, colorants such as pigments and dyes, extender pigments, solvents, and various additives contained in ordinary inks are added. Particularly frequently used pigments include condensed azo, insoluble azo, quinacridone, isoindoline, anthraquinone, imidazolone, cobalt, phthalocyanine, carbon, titanium oxide, iron oxide, mica and other pearl pigments.
[0048]
In any decorative sheet 2, a primer coat for bonding to the wood resin foam molded body 1, a top coat for surface protection and gloss adjustment, a conduit expression by an embossing method or a gloss mat method, etc. It may be given. Moreover, the additive used for the thermoplastic resin layer in the decorative sheet 2 can be used as appropriate as in the wood resin foam molded article 1.
[0049]
The thickness of the decorative sheet 2 is not particularly limited, but is usually in the range of about 0.05 to 0.3 mm. The lamination method of the decorative sheet 2 and the wood resin foam molded body 1 is not particularly limited. For example, a dry lamination method or a wet lamination method using an adhesive, a thermal lamination method using or not using an adhesive, or an ultrasonic fusion. Conventionally known methods such as a method for forming and laminating a decorative sheet 2 in a cooling sizing mold at the same time as foam extrusion molding of a wood resin foam molded body 1 and a method of high frequency fusion bonding, and a pasting method may be arbitrarily used. it can.
[0050]
In the present invention, the surface of the wood resin foam molded body 1 on which the decorative sheet 2 is laminated does not necessarily refer to the entire surface including the upper surface, the lower surface, and the side surfaces, but at least the upper surface that becomes an exposed surface when applied to the floor surface. It suffices if they are laminated. And as needed, it can also be set as the structure laminated | stacked continuously from the upper surface to a part or all of a side surface, or passing through all the side surfaces and a part of the lower surface. When the decorative sheet 2 is laminated over at least a part of the side surface, there is an advantage that the gap between the flooring materials is less noticeable when the decorative sheet 2 is applied to the floor surface.
[0051]
In many cases, the side surface of the woody resin foam molded body 1 as a base material of the flooring material of the present invention is provided with a fitting structure such as a male and female fruit for connecting the flooring materials to each other. In this case, in order to ensure the strength and dimensional accuracy of the fitting structure portion, it is desirable that the fitting structure portion is non-foamed or in a low foamed state with a foaming ratio of 1.5 times or less. According to the above-mentioned SELKA process, the fitting structure part becomes a thin part of an intricate structure, so that the contact area with the cooling sizing mold increases, and a non-foamed or low-foamed fitting structure part is easily formed. There are advantages that can be done. Further, when the fitting structure portion is provided in this way, the decorative sheet 2 is laminated continuously from the upper surface over at least the surface of the wood resin foam molded body 1 that can be seen from the surface side in the fitting connection state. It is desirable to keep it.
[0052]
Further, the floor material of the present invention is similar to the thermoplastic resin 13 contained in the wood resin foam molded body 1 on a part or all of the surface of the wood resin foam molded body 1 on which the decorative sheet 2 is not laminated. A foam layer (not shown) mainly composed of the thermoplastic resin may be laminated. For example, if a foam layer is laminated on the back side of the flooring, it absorbs the unevenness of the floor surface and prevents rattling, or absorbs the impact sound and walking sound of articles on the floor. There are effects such as preventing.
[0053]
For the method of laminating the foamed layer, a known method can be used. For example, the thermoplastic resin similar to the thermoplastic resin used in the foamable wood resin composition for molding a wood resin foam molded article is used for the above pyrolysis and chemicals. A foamed molded article formed by foaming a sheet with a foaming agent that is either a chemical foaming agent that generates gas by reaction or a physical foaming agent that vaporizes by applying heat to a low-boiling liquid, and is a decorative sheet for a wood resin foam molded body Can be formed by adhering to a part or all of the non-laminated surface.
[0054]
When recycling the flooring of the present invention, the decorative sheet 2 laminated on the surface is crushed as it is without being peeled off, and a wooden filler, a thermoplastic resin, various additives and the like are added as necessary. Then, it can be pelletized again, and this can be reused as a molding material for the woody resin foam molding 1. Also in this case, the method for kneading the crushed material, the pelletizing method, the forming method, etc. is not particularly limited. Further, instead of re-pelletizing, the crushed material is directly put into a molding machine as a molding material for the wood resin foam molded body 1, or when the wood resin foam molded body 1 is molded, the crushed material and the wooden filler or thermoplastic resin are used. Of course, it is also possible to put in the molding machine at the same time, and molding while kneading in the molding machine.
[0055]
【Example】
Specific examples of the present invention will be described below.
[0056]
Example 1
100 parts by weight of a homopolypropylene resin having a bending elastic modulus of 1000 MPa, which is obtained by adding 20% by weight of a maleic acid-modified homopolypropylene resin to a homopolypropylene resin, and the wood is broken by a cutter mill, which is pulverized by a ball mill and finely powdered. 100 parts by weight of a wood filler having an average particle size of 100 μm was mixed by a twin-screw extrusion kneader and pelletized to prepare a wood resin composition. A baking soda-citric acid-based foaming agent was added to this woody resin composition, and the foaming ratio was applied to the surface of a core part having a foaming ratio of 1.54 times and a thickness of 4.6 mm by a Celca process using a single screw extruder. A wood resin having a surface layer portion of 1.08 times and a thickness of 0.7 mm, formed into a rectangular section with an average expansion ratio of 1.4 times, a thickness of 6 mm and a width of 300 mm, and further subjected to corona discharge treatment on the surface. A foamed molded product was produced.
[0057]
On the other hand, 100 μm colored polypropylene sheet formed by blending pigments such as iron oxide and titanium oxide with random polypropylene was printed with urethane ink, and homopolypropylene resin was made to a thickness of 100 μm by extrusion lamination method. A decorative sheet laminated simultaneously with embossing was prepared, and a primer coat was applied to the back surface and a top coat was applied to the surface to prepare a decorative sheet made of polypropylene resin. Thereafter, this decorative sheet was bonded to the surface of the wood resin foamed molded article by a lapping method to produce the flooring of the present invention.
[0058]
Comparative Example 1
In the above Example 1, instead of the Celca process, a normal free process (a foam extrusion method in which a foamable wood resin composition is extruded from an extrusion mold and then sufficiently foamed and then introduced into a cooling sizing mold). To form a woody resin foam molded body having the same cross-sectional shape as in Example 1, which is foamed at a foaming ratio of 1.4 times without forming a surface layer portion and a core portion. A flooring was produced in the same manner as in Example 1.
[0059]
Comparative Example 2
In Example 1 above, by changing the molding conditions, the foaming ratio of the core part was changed to 1.44 times, the foaming ratio of the surface layer part was changed to 1.28 times, and the others were the same as in Example 1 above. Floor material was prepared.
[0060]
Comparative Example 3
In Example 1 above, by changing the molding conditions, the thickness of the core part is changed to 1.6 mm, the thickness of the surface layer part is changed to 2.2 mm, and the rest is the same as in Example 1 above. A material was prepared.
[0061]
Comparative Example 4
In Example 1 above, a polypropylene resin having a flexural modulus of 600 MPa was used instead of the polypropylene resin having a flexural modulus of 1000 MPa as the thermoplastic resin used for the production of the wood resin foam molded article, and the others were carried out as described above. A flooring was produced in the same manner as in Example 1.
[0062]
Comparative Example 5
In Example 1, a polypropylene resin having a flexural modulus of 3200 MPa was used in place of the polypropylene resin having a flexural modulus of 1000 MPa as the thermoplastic resin used for the production of the wood resin foam molded article. A flooring was produced in the same manner as in Example 1.
[0063]
Performance Comparison About the flooring materials of Example 1 and Comparative Examples 1 to 5, a commercially available wood flooring material (a 0.5 mm thick oak veneer was laminated on the surface of a 6 mm thick laminated plywood and painted) A steel ball drop test (referred to as Comparative Example 6 hereinafter) and a cushion floor (hereinafter referred to as Comparative Example 7) together with a steel ball drop test (a sample is placed on a concrete surface, a steel ball having a weight of 535 g is naturally dropped from a height of 75 cm, and dent Depth [mm]), surface hardness test (DD2 rubber hardness tester), DuPont impact resistance test, pencil hardness test, caster resistance test (nylon wheel, load 30 kg, 1 wheel, 200 reciprocations) and pressure proof When performance evaluation was performed in a test (nylon wheel caster, load 20 kg, 1 wheel, 40 ° C. for 5 days), the results were as shown in the table below.
[0064]

[0065]
Further, when walking on the floor surface constructed using each of the above floor materials with bare feet and examining the tactile sensation and the walking sensation, the floor material of the comparative example 3 is poor in the cold sensation and walking sensation. The poor feeling of walking was pointed out for each, but the others were results without any problems.
[0066]
【The invention's effect】
As explained in detail above, the flooring of the present invention is based on a wood resin foam molded article containing a thermoplastic resin and a wood filler, and the surface of the floor material is the same as the thermoplastic resin which is the main component of the base material. In addition to being excellent in wood texture, machinability, and recyclability, by laminating decorative sheets made of thermoplastic resin, the foaming ratio and thickness of the core and surface layers are within a specific range. By setting the initial flexural modulus of the thermoplastic resin, which is the main component of the base material, to a specific range, heat insulation (feeling of warmth), walking feeling, surface hardness, impact resistance, scratch resistance, scratch resistance, construction The present invention has a remarkable practical advantage in that it can provide a floor material having excellent performance suitable as a substitute for a conventional wooden flooring material that is balanced in terms of aptitude and the like.
[Brief description of the drawings]
FIG. 1 is a side sectional view showing an embodiment of a flooring of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Wood resin foam molding 11 Core part 12 Surface layer part 13 Thermoplastic resin 14 Wood type filler 15 Air bubble 2 Cosmetic sheet

Claims (4)

A makeup mainly comprising a thermoplastic resin similar to the thermoplastic resin contained in the wood resin foam molded body on the surface of the foamed wood resin foam molded body containing a thermoplastic resin and a wood based filler. A flooring material in which sheets are laminated, and the wood resin foam molded body has a foaming ratio of 1.0 to 1.1 times, a surface layer part having a thickness of 0.1 to 2 mm, and a foaming ratio of 1. The thermoplastic resin contained in the wood resin foam molded body is a polyolefin resin having a bending initial elastic modulus of 700 to 3000 MPa. Flooring. The flooring material according to claim 1, wherein the wood-based filler has an average particle diameter of 1 to 200 µm and is blended in an amount of 10 to 500 parts by weight with respect to 100 parts by weight of the thermoplastic resin. The flooring material according to claim 1 or 2, wherein the woody resin foam molding is formed by a Celca process. The flooring material according to any one of claims 1 to 3, wherein the decorative sheet has a thickness of 0.05 to 0.3 mm.

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